Mobility aid

ABSTRACT

The present invention provides a system (10, 110) for aiding a user to move, comprising: a sensor (20, 120) configured to detect a parameter indicating a position of the user&#39;s foot; a feedback device (30, 130) operable to provide feedback to the user; and a processor, wherein the processor is configured to control the feedback device (30, 130) depending on the sensed parameter. The present invention is beneficial because it increases confidence and/or efficiency in movement, providing visual aids and/or tactile feedback to guide the user.

FILED OF THE INVENTION

THE PRESENT INVENTION relates to a mobility aid and more particularly toan aid that provides visual cues and/or tactile feedback for a user.

INTRODUCTION

The present invention relates to a mobility aid to assist in theeveryday life of a person with mobility issues. Posture and balance forwalking in particular are intricately linked to proprioception, theability to sense the position, location, orientation and movement of thebody and its parts. Proprioception and other sensory feedback is oftenimpaired in patients with diseases such as multiple sclerosis (MS) andParkinson's disease (PD) for example. These diseases often result unevenwalking.

For example, in normal gait, the heel strikes the ground before the toes(heel-to-toe walking). In Parkinsonian gait, the entire foot is oftenplaced on the ground at the same time, or the toes touch the groundbefore the heel. In addition, PD patients may have reduced foot liftingclearance between the toes and the ground. Postural instabilityincreases the likelihood of a patient falling, the consequences of whichare obvious.

This invention is also helpful for other persons with lessened sensoryfeedback. It can also be helpful in sports for people with no mobilityissues, but who wish to receive active feedback on their posture orgait, to review and revise their posture/gait e.g. when running. Thedevice may also be helpful for anyone during general walking, to predictand detect changes in walking.

The present invention aims to provide a mobility aid to enhance a user'sability to move stably and/or efficiently. The invention can also reducethe risk of the user falling.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a system and method for aiding a user asclaimed.

In particular, the present invention provides a system for aiding a userto move, comprising: a sensor configured to detect a parameterindicating a position of the user's foot; a feedback device operable toprovide feedback to the user; and a processor, wherein the processor isconfigured to control the feedback device depending on the sensedparameter.

Preferably, the present invention provides a system for aiding a user tomove, comprising: a sensor configured to detect a parameter indicating aposition of the user's foot; a projector operable to project a firstvisual cue; and a processor, wherein the processor is configured tocontrol the projector depending on the sensed parameter.

Preferably, the present invention provides a system for aiding a user tomove, comprising: a sensor configured to detect a parameter indicating aposition of the user's foot; a motor operable to provide vibrationalfeedback in response to the sensor output; and a processor, wherein theprocessor is configured to control the vibrational feedback depending onthe sensed parameter.

The present invention is beneficial because it increases confidenceand/or efficiency in movement—it provides visual aids and/or tactilefeedback to guide the user. It also promotes independence. Further, theinvention is environmentally-friendly, because it promotes travel bywalking.

Embodiments of the present invention will now be described, by way ofexample only, with reference to the following figures, in which:

FIGS. 1 and 2 show schematic overviews of the present invention;

FIG. 3 shows a shoe comprising an attachment illustrating a firstembodiment of the present invention;

FIGS. 4 and 5 show the embodiment of FIG. 3 in more detail;

FIGS. 6 and 7 illustrate how two visual cue mechanisms operate inrelation to a user's stride according to the first embodiment;

FIG. 8 illustrates an electronic layout for the first embodiment of thepresent invention;

FIG. 9 illustrates how two different visual cue feedback mechanisms mayoperate in response to sensed pressure according to one embodiment;

FIG. 10 illustrates an insole embodying the present invention;

FIG. 11 illustrates how a vibrational feedback mechanism embodying theinvention may operate in response to sensed pressure;

FIG. 12 illustrates a method for determining the optimal angle ofprojection; and

FIG. 13 illustrates an electronic layout for the vibrational feedbackmechanism of FIGS. 10 and 11.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is illustrated in FIG. 1, which shows the coreelements of the system 10: a sensor 20 for sensing a parameterindicating a position of the user's foot and a feedback device 30 toprovide feedback to enhance proprioception and sensory feedback.

In a first embodiment, the feedback device 30 is a projector in the formof a laser, and the laser provides one or more visual cues in responseto the sensed parameter, to aid the user in walking. In the firstembodiment, the sensor 20 is a pressure sensor, detecting the pressureexerted by the user on a surface such as the ground. In otherembodiments, a distance sensor is used.

In use, the pressure sensor 20 measures the contact pressure between theuser's foot and the walking surface. When the user's foot touches thesurface and the sensed pressure exceeds a threshold, a line projectionis emitted by the laser, indicating a path for the user to travel along.When the sensed pressure falls below the threshold, the laser isswitched off, to preserve battery life.

A preferred implementation of the laser line projection is illustratedin FIGS. 3-5. In these figures, the laser projector 30 comprises threelaser elements: two lower line projection laser elements 31 and an upperdot projection element 32. The two lower laser elements are arranged toproject at an angle of substantially 45-60° to provide a suitablediverging walking path. The dot projection is focused above the lineprojections, so that it reflects off obstacles in the user's path.

In the preferred arrangement shown, the two laser elements 31 are placedat the front of the shoe. This is a preferred location for the laserelements 31 because it is the last area to move out of contact with theground surface during the gait cycle. The angle of the projection variesaccording to the individual user. The angle of the projection determinesthe projection distance from the shoe and is influenced by the gaitstride and size of the user. This is discussed further with reference toFIG. 11 below.

In other embodiments, the laser projection may comprise a differentnumber of laser elements 31—for example one laser element 31 may beconfigured to provide both the line and dot projections, switchingbetween the two.

In preferred embodiments, the visual cues comprise two elements: lineand dot projections. The line projections provide a path for the user tofollow. In terms of overcoming fear of falling and promoting movement,there are different needs for different users. MS patients will have aneed for the path (line) projection, whereas PD users suffering from FOG(freezing of gait) need obstruction identification/projection. For bothtypes of users, the dot projection is a guideline for avoidingobstacles. Preferably, the dot projection (obstacle identification) ispresented when a foot is not touching the surface and the sensedpressure is below a threshold. In some embodiments, the thresholds forthe dot and line projections are the same, so the system switchesbetween line and dot projections as the user walks. In otherembodiments, the thresholds are not the same, and may overlap. In otherembodiments, the dot and/or line projections may also be “on”,regardless of any thresholds.

Preferably, the dot projection has a diameter and brightness that makesit easily visible for the user to identify obstacles. These dotprojection parameters can be determined by the particular objects thatthe user finds difficulty in avoiding, e.g. steps. Since steps are to beavoided at a short distance, the required diameter of the projection maybe relatively small, e.g. at least 3 mm at 0.2 m or less from the stepobstacle. For obstacles that need to be avoided early, e.g. bins or lampposts that must be walked around, the same diameter may be required at adistance of 0.5 m or less, and these parameters would still be suitablefor steps (but increase power consumption).

In other embodiments, such as sports training, other types of projectionmay be required to e.g. advise the user on the best steps to pursue inorder to enhance performance. Preferably, these parameters can beconfigured by the user.

In some embodiments, the system further comprises a distance orproximity sensor for detecting the distance to/presence of obstacles,and the system is configured to provide a visual cue such as a dotprojection to highlight the obstacle, in response to the sensorfeedback. Accordingly, the dot projection parameters may be configuredby the system automatically, using the sensor information. The systemmay optionally provide additional audible, vibrational or visualfeedback when the obstacle is within a predetermined proximity/distance.

The combined path and obstacle identification system is illustratedschematically in FIG. 2. Here, the shoe clip is attached on the front ofthe user's shoe, as shown in FIG. 3, where a path is projected from theright shoe of the wearer. This guidance path helps when moving the leftfoot that is currently travelling. Once the left foot is on the ground,it will similarly project a path for the right foot to follow. The shoeclip is preferably connected to the insole via a wireless connectionsuch as Bluetooth® but it may also be hard wired. The insole informs theactivity in terms of laser projection from the shoe clip (FIG. 2, step 2a), where a guidance pathway is projected from the user via ‘PathFinder’. As the user approaches an obstacle, the visual stimuli willhelp to alert the user whether it is safe to pass (FIG. 2, step 2 c).Pressure observed in the insole is used to determine which laser is onat which time, as explained further below, and tactile feedback mayoptionally be given for each step indicating surface hardness through‘Path Feel’ (FIG. 2, step 2 b). The programming of events can be changedand customised for different scenarios. For instance, the need inhealthcare may be different to the need in sports scenarios.

In some embodiments, the laser component can be turned 90 degrees, toproject vertically (4 a) and/or horizontally (4 b). This 90° rotation isillustrated in FIGS. 4 and 5, where the laser element is placed at thefront of the shoe (FIGS. 4a and 4b ). Alternatively, an opticaldiffractive element may be used. The different projections are used forthe different needs of users. For example, an MS user may observeincreased confidence when being supported by the visual path which actsas guidance. The PD user benefits from having obstruction projected;particularly patients suffering from FOG. The obstructions are visualcues that can help to trigger movement, when the user is otherwise in a‘frozen’ state.

FIGS. 6 and 7 illustrate the interactions between the visual cues andthe user's feet positions whilst walking. In summary, the lineprojection (path indication) is presented when the user's foot touchesthe surface and the sensed pressure exceeds a threshold. The dotprojection (obstacle identification) is presented when a foot is nottouching the surface and the sensed pressure is below a threshold. Inthis way, the feet act together in a coordinated fashion to support themovement of each other, e.g. the left foot projects for the right andvice versa. In FIG. 6, the projector is horizontal as FIG. 4b and theline projection is in the direction of the user's intended path. In FIG.7, the line projection is ‘vertical’, as shown in FIG. 4 a. The‘horizontal’ projection projects a path for the user to follow and the‘vertical’ projection projects a step interval e.g. in the form of twoparallel, vertically spaced-apart lines for highlighting obstacles. Insome embodiments, the vertical projection is paired with distancesensors to measure a distance to the obstacle(s), preferably providingan output in response to the sensed distance.

FIG. 8 illustrates an electronic layout for the first embodiment of thepresent invention. The laser projections are influenced by the pressurecoming from the insole (illustrated in FIGS. 6 and 7 and by the sensorplaced in the electronic layout). The dot projection is ON when there isno pressure, and the foot is travelling, at which point the lineprojection is OFF on that foot. The opposite foot will have the reversetiming, and i.e. when the right foot is travelling, the left foot is onthe ground, thereby activating pressure. When pressure is on, the laserline is ON and the dot projection is OFF. It is possible for the user toswitch off the entire system using a main switch. The system ispreferably also configured to turn off automatically after a given timewhen the pressure is substantially constant and it can be assumed thatthe user is standing still (constant high pressure) or seated (constanthigh, low or zero pressure, depending on the support of the feet).

FIG. 9 illustrates how the line and dot visual feedback mechanisms mayoperate in response to the sensed pressure. Here, there are threepressure sensors 20: forefoot 21, mid foot 22 and rear foot 23. In theillustrated embodiment, the line projection is enabled when any sensordetects pressure from the user's foot contacting the floor. The dotprojection is enabled when none of the sensors detect a pressureindicating contact with the floor. In the illustration of FIG. 9, both‘horizontal’ and ‘vertical’ line projections are shown. In embodiments,any combination of the line (horizontal and/or vertical) and/or dotprojections may be used.

In some embodiments with multiple sensors 20, the threshold for the lineprojection is preferably linked to both the toe (or forefoot) sensor 21and the heel (or rear-foot) sensors 23, since the heel sensor is thefirst to touch down and activate the line projection and the toe sensoris the last to leave the ground in the gait cycle. Accordingly, the lineprojection may be activated when the toe and/or heel sensors 21,23 sensea pressure exceeding the pressure threshold; and deactivated when bothsensors sense a pressure below the threshold. For a distance sensor, theline projection may be activated when the toe and/or heel sensors sensea distance below the distance threshold; and deactivated when both sensea distance exceeding the threshold. The appropriate thresholding cansimilarly be applied for other sensors. Of course, some users may havedifferent gait cycles and hence different needs, for instance if theysuffer from foot-drop.

The threshold for the dot projection is also preferably linked to thetoe and/or heel sensors for the same reason. Here, the functionality ofthe projector (both line and dot projections) is solely determined bythe sensed parameter(s) of the elected threshold sensor(s)—the othersensors do not affect the switching of the projector. Depending on theuser's gait, other sensors or combinations thereof may be the elected‘threshold’ sensors.

In some embodiments, the sensors 20 work collectively and the sensedparameter is determined as an average or sum of the separate sensoroutputs. In some embodiments, particular sensors may be weighted in thecalculations. In some embodiments, only one of the line and dotprojections is provided; in others, both are provided.

In the embodiments shown, three lasers are used to project two lines andone dot. The timing of each event is determined by the gait of thewearer. Other ways of projecting laser may include the use of fewer ormore laser elements, e.g. one or two lasers.

For the line projection, a suitable force (or equivalent pressure)threshold for enabling the projection might be ≥45% or ≥50% of theuser's weight detected by the sensor(s) on a single foot. When thedetected force is substantially equal to the user's weight, thisindicates that only that foot is touching the ground. When the detectedforce is substantially half the user's weight, this indicates that bothfeet are in contact with the ground, each supporting approximately 50%of the force (thus a 45% threshold provides a 10% margin of error orimbalance).

For the dot projection, a suitable force (pressure) threshold forenabling the dot might be 0% of the user's weight, or even substantiallyzero, so the foot is only lightly supporting the user, or not at all. Inother embodiments, alternative thresholds are used, e.g. a single(substantially) zero threshold: if there is no pressure detected thenthe dot projection is enabled; and any non-zero pressure enables theline projection.

In a second embodiment, the present invention provides a feedback devicein the form of a motor, wherein the motor provides vibratory feedback inresponse to the sensed parameter. In some embodiments, the motor isimplemented within an insole of footwear.

The insole provides tactile feedback in order to give the user anincreased somatosensory feedback and proprioceptive understanding andsensory feedback in general. The insole can be personalised to fit thefeet of each user, and provide the required support and feedback,however, a generalised insole may be used in some applications. Eachuser may also have different levels of sensory perception depending onthe level of impairment, hence different vibrational levels may beneeded. These settings are preferably adjustable when the user initiallycalibrates the insole. The calibration may be completed using an app ona smartphone or similar.

In the second embodiment, the insole comprises a pressure sensor 120 anda vibration motor 130. The pressure sensor 120 detects changes inpressure and amount of pressure, allowing the vibration feedback to bedirectly (or inversely) correlated with the amount of pressure. Hence,different surfaces result in different amounts of vibration, thevibration varying in direct or inverse proportion to the pressure. It istherefore possible for a user to detect the hardness of a surface, ase.g. stepping in mud will give less strong vibrations than stepping ontoa concrete surface (mode 1). With inverse correlation, stepping in mudwill give stronger vibrations than stepping onto a concrete surface(mode 2). In other embodiments, the vibration level operates like atraffic light system having three tiers indicating the rigidity of thesurface to the user, rather than proportional correlation, as tabulatedbelow:

Surface Mode 1 Mode 2 Concrete (stable, solid) Strong vibration Mildvibration Mud (moderate) Moderate vibration Moderate vibration Sponge(unstable) Mild vibration Strong vibration

For other purposes, the vibration may be used to guide and train thewearer. In sports scenarios, it could be used for performanceenhancement by vibrating when the wearer needs to run faster to improvetheir time over a given distance. It could also be used to correctrunning gait by measuring posture and providing corrective feedbackaccordingly.

Alternatively, multiple distance sensors could be used and the systemcan determine whether the distance from the underside of the foot to thesurface at multiple locations, and thus whether the surface is flat oruneven. In some embodiments, pressure is observed in three locations, atthe forefoot with sensor 121, mid foot with sensor 122 and rear footwith sensor 123. Vibrational feedback may optionally be provided in thesame three locations with the respective forefoot motor 131, mid footmotor 132 and rear foot motor 133.

The increased proprioceptive and sensory feedback will come through thevibration motors 130 placed within the insole and activated by feedbackfrom the pressure sensors 120. Additionally, the insole can becustomised to the individual, providing touch on the entire sole of thefoot, as opposed to what most people have today—a flat shoe, that onlyprovides touch on the pressure points at the front and heel of the foot.In other embodiments, vibrators may be located remotely from the insole,e.g. on a wristband, to stimulate other parts of the user inuse—particularly if the user is has a low touch sensitivity at theirfeet. In the case of amputees, there may also be other locations used totransfer the sense of touch from the feet or other body part.

Exemplary insoles and a moulded prototype are shown in FIG. 10. FIG. 10shows four images: a) a visualization of the sensory feedback providedfrom the ground (via the insole) using haptics in the form of vibration;b) an upper view of the upper layer; c) a lower view of the upper layer;and d) an upper view of the lower layer. The electronic parts sitbetween the upper and lower layers.

As shown in FIG. 10 d, in this embodiment pressure is observed in threelocations, at the forefoot with sensor 21, 121, mid foot with sensor 22,122 and rear foot with sensor 23, 123. Vibrational feedback mayoptionally be provided in the same three locations with the respectiveforefoot motor 131, mid foot motor 132 and rear foot motor 133.

A schematic of the vibrational activation is shown in FIG. 11. In thisembodiment, when there is no pressure, there is no vibration. Here, asthe pressure increases, the vibrational feedback increases. As specifiedabove, the pressure-feedback can be supplied in a number of waysdepending on the use and the requirements from the user. In theembodiment described in FIG. 11, the vibrational feedback is provided indirect proportion to the pressure observed. In other embodiments, thefeedback may be used in other ways, such as to influence running gait orto enhance performance as a training device. It may also be used tocorrect posture, in which case the haptic feedback may again be useddifferently.

FIG. 12 illustrates the placement of the optical element for the lineprojection. For the creation of a dot projection, no optical element isnecessary. The optimal projector location is the top of the forefoot, asthis is the last place to move during the gait cycle. It is therefore astable place from which to project. The angle of the projection elementused is determined by the user's gait and needs.

For instance, in order to project at a distance of 500 mm from thesource (the shoe of the wearer), a fan angle of 45 degrees will providea line which is approximately 410 mm in length. Should the desiredprojection distance from source be 400 mm, a fan angle of about 55degrees provides a line of the same length as in the previous example.These figures are calculated from manufacturer's data, available onlineat http://www.global-lasertech.co.uk/line-fan-angle-calculator/.

FIG. 13 illustrates an electronic layout for the second embodiment ofthe present invention. The vibration motor(s) are activated by thepressure sensor(s) as discussed above. An Inertial Measurement Unit maybe included in some embodiments to provide information about balance,velocity, orientation and gravitational forces, and being able to derivefurther information about the wearer's gait. Combining IMU sensor datawith pressure sensor data enhances the accuracy of the foot positionmonitoring capability.

In the first embodiment, the pressure sensor 20 is used to detect theposition of the user's foot, which may be determined as a binary contactstatus: in contact with a surface, or not in contact with a surface. Inother embodiments, the position is detected to a degree using a pressuresensor 120 or distance sensor.

The preferred embodiments use a pressure sensor 20, 120 to measure apressure exerted by the user on a surface. In other embodiments, anyother sensor may be used, such as a proximity sensor, a light sensor ora distance sensor (e.g. ultrasound, IR). Preferably, data is collectedby the sensors, which also observe the behaviour of the wearer, makingit a two-way interaction between user and sensors. The sensors impactthe feedback mechanisms (both visual and tactile) via themicrocontroller that analyses the sensor input and converts it into anoutput. The output is preferably real-time with minimal delay, but inputcan also be stored for future analysis.

In a preferred embodiment, three pressure sensors 120 (121, 122 and 123)and three vibration motors 130 (131, 132, 133) are used. The sensors 120and motors 130 are paired together and located at the heel (rear foot),toe (forefoot) and under the arch of the foot (mid foot). These pairsare linked individually—i.e. if only the toe of the wearer is on theground, then only the motor in the toe area will vibrate. Likewise, ifonly the heel is on the ground, only the motor in the heel area willvibrate. This arrangement is beneficial as the vibrational feedbackdirectly correlates to the contacting area. Other embodiments mayinclude more or fewer sensors 120 and motors 130 and other pairings.

In the illustrated embodiments, the system is implemented as one or moreattachments for footwear. In other embodiments, the system may beintegrated within footwear.

The present invention may also be used to gather user data and correlateuser data with the feedback. The present invention may further comprisean input device for receiving user data such as medical (disease andmedication) history and biometric data. The present invention mayfurther comprise storage to store this data and the sensor data, toidentify trends in the data. The system may further comprise a wirelesscommunications element to send and receive such data e.g. to asmartphone or smartwatch or directly to a computer or other storagefacility, such as a memory card. In particular, the system may beoperable to record pressure sensor data across the user's foot inreal-time and store/transmit this data for real-time analysis of weightdistribution, for example. The tactile feedback may be used to “train”the user to modify their weight distribution e.g. for improvedperformance, stability or strength as described above.

This data may be used to track disease progression (by the user, medicalprofessional or in research), to link with medication that the user maybe taking, as it may be that drug A is best for user A and drug B isbest for user B, even if they are diagnosed with the same disease. Overtime, it may also be possible to identify trends, that can be used forresearch purposes, to better understand the disease. The data mayfurther help with diagnosis and in evaluation of clinical trialsregarding new treatment and medication methods.

In the preferred embodiments, a vibration motor(s) where the forcedirection is vertical is used, as the human body is designed to absorbforces in a vertical direction. Vibration in a vertical direction mayalso increase circulation and lymphatic drainage, whilst improvingproprioception, balance and posture.

When used in this specification and claims, the terms “comprises” and“comprising” and variations thereof mean that the specified features,steps or integers are included. The terms are not to be interpreted toexclude the presence of other features, steps or components.

The features disclosed in the foregoing description, or the followingclaims, or the accompanying drawings, expressed in their specific formsor in terms of a means for performing the disclosed function, or amethod or process for attaining the disclosed result, as appropriate,may, separately, or in any combination of such features, be utilised forrealising the invention in diverse forms thereof.

Preferred Features

1. Footwear or an attachment for footwear to assist a person walking ina direction of travel, e.g. a person with limited or impaired walkingability, comprising a device for projecting a line in front of theperson wearing the footwear, the line either forming a path extending inthe said direction of travel or a line extending across the direction oftravel, e.g. at right angles to the direction of travel.

2. Footwear or an attachment for footwear as recited in clause 1,wherein the device is switchable between projecting a line forming apath extending in the said direction of travel and a line extendingacross the direction of travel.

3. Footwear or an attachment for footwear as recited in clause 1 orclause 2, wherein the device is capable of projecting a spot in front ofthe person wearing the footwear to assist in gauging the height of anobstacle lying along the direction of travel.

4. Footwear or an attachment for footwear as recited in any precedingclause, which comprises a pressure-sensor for detecting the pressureexerted by the person's foot on the ground, which sensor is capable ofcommunication with the device to project a line only when the sensordetects a pressure above a predetermined threshold value.

5. Footwear or an attachment for footwear as recited in clause 4,wherein the device is configured to project a spot when the sensordetects a pressure below a threshold value.

6. Footwear or an attachment for footwear as recited in clause 4 orclause 5, which includes an insole and wherein the sensor isincorporated into the insole.

7. Footwear or an attachment for footwear as recited in clause 6,wherein the insole includes a vibrator capable of delivering a variabledegree of vibration to the sole of the person's foot, which the sensoris capable of communication with the vibrator to provide a degree ofvibration that increases with increasing pressure sensed by the sensor.

8. A method of assisting a person with walking in a direction of travel,e.g. a person with limited or impaired walking ability, which comprisesprojecting from the person's foot a line in front of the person, theline either forming a path extending in the said direction of travel ora line extending across the direction of travel, e.g. at right angles tothe direction of travel.

9. A method as recited in clause 8, which compromises projecting a spotin front of the person wearing the footwear to assist in gauging theheight of an obstacle.

10. A method as recited in any preceding clause 8 clause 9, whichcomprises sensing the pressure exerted by the person's foot on theground, and projecting a line only when the sensor detects a pressureabove a predetermined threshold value.

11. A method as recited in clause 10, which comprises projecting a spotwhen the pressure is below a threshold value.

12. A method as recited in clause 10 or clause 11, wherein a vibrationis delivered to the sole of the person's foot and wherein the degree ofvibration increases with increasing pressure sensed by the sensor.

13. A system for aiding a user to move, comprising:

-   -   a sensor configured to detect a parameter indicating a position        of the user's foot;    -   a projector operable to project a first visual cue; and    -   a processor, wherein the processor is configured to control the        projector depending on the sensed parameter.

14. The system of clause 15, wherein the system is further operable toproject a second visual cue, different to the first visual cue.

15. The system of clause 14, wherein:

-   -   the first or second visual cue is a line projection indicating a        path extending in a direction of intended travel; and/or    -   the first or second visual cue is a dot projection.

16. The system of any of clauses 13 to 15, wherein the sensor comprisesa pressure or distance sensor and the processor is configured to enablethe first and/or second visual cue when the sensed pressure or distanceis above a threshold value.

17. The system of any of clauses 13 to 15, wherein the sensor comprisesa pressure or distance sensor and the processor is configured to enablethe first and/or second visual cue when the sensed pressure or distanceis below a threshold value.

18. The system of any of clauses 13 to 15, wherein the sensor comprisesa pressure or distance sensor and the processor is configured to:

-   -   enable the first or second visual cue when the sensed parameter        is above a first threshold value; and    -   enable the other of the first and the second visual cues when        the sensed parameter is below a second threshold value.

19. The system of any of clauses 16 to 18, wherein the first and secondthreshold values are substantially the same.

20. The system of any preceding clause, wherein the system furthercomprises a motor, operable to provide vibrational feedback in responseto the sensed parameter.

21. A system for aiding a user to move, comprising:

-   -   a sensor configured to detect a parameter indicating a position        of the user's foot;    -   a motor operable to provide vibrational feedback in response to        the sensor output; and    -   a processor, wherein the processor is configured to control the        vibrational feedback depending on the sensed parameter.

22. The system of clause 20 or 21, wherein the strength of the vibrationis configured to increase as the sensed pressure increases or the senseddistance decreases.

23. The system of any preceding clause, wherein the position of the footis either:

-   -   in contact with a surface, or    -   not in contact with a surface.

24. The system of any preceding clause, further comprising a wirelesscommunications module for transmitting and/or receiving data.

25. The system of any preceding clause, in the form of footwear or anattachment for footwear.

26. The system of clause 12, in the form of footwear or an attachmentfor footwear, wherein:

-   -   the sensor is a pressure sensor configured to detect a pressure        exerted by the user's foot on a surface;    -   the first visual cue is a line projection for indicating a path        extending in a direction of intended travel;    -   the system is operable to project a second visual cue in the        form of a dot projection for highlighting obstacles; and    -   the processor is configured to enable the first visual cue when        the sensed pressure exceeds a threshold and to enable the second        visual cue when the sensed pressure is below the threshold.

27. A method for aiding a user to move, comprising:

-   -   measuring sensor data from a sensor configured to detect a        position of the user's foot; and    -   projecting a first visual cue indicating a direction of intended        travel, depending on the sensed parameter.

28. The method of clause 27, wherein the method comprises:

-   -   detecting when the user's foot is in contact with a surface; and    -   projecting a first visual cue from a projector when the user's        foot is in contact with the surface.

29. The method of clause 27 or 28, further comprising:

-   -   projecting, from the user, a second visual cue, different to the        first visual cue, for identifying obstacles;    -   receiving and storing user data; and/or    -   providing tactile feedback from a motor in response to the        sensed pressure.

30. The method of any of clauses 27 to 29, wherein:

-   -   the first or second visual cue is a line projection indicating a        path extending in a direction of intended travel; and/or    -   the first or second visual cue is a dot projection.

31. The method for aiding a user to walk of clause 27, wherein thesensor comprises a pressure sensor and the method involves:

-   -   measuring sensor data from the pressure sensor; and    -   projecting a first visual cue in the form of a line projection        indicating a path extending in a direction of intended travel        from a projector, when the sensed pressure is above a threshold        value.

32. The method for aiding a user to walk of clause 27, wherein thesensor comprises a pressure sensor and the method involves:

-   -   measuring sensor data from the pressure sensor;    -   projecting a first visual cue in the form of a line projection        indicating a path extending in a direction of intended travel        from a projector when the sensed pressure is above a threshold        value; and    -   projecting a second visual cue in the form of a dot projection        for highlighting obstacles when the sensed pressure is below the        threshold value.

33. The method of any of clauses 27 to 32, wherein the sensor comprisesone or more pressure sensors and the method comprises measuring thepressure values to determine the user's weight distribution.

34. A method for aiding a user to walk, comprising:

-   -   measuring sensor data from a sensor configured to detect a        position of the user's foot; and    -   providing tactile feedback from a motor in response to the        sensed parameter.

35. The method of clause 34, wherein the strength of the vibration isconfigured to increase as the sensed pressure increases or the senseddistance decreases.

1-24. (canceled)
 25. A system for aiding a user to move in the form offootwear or an attachment to footwear, the system comprising: a sensorconfigured to sense pressure exerted by the user's foot; a motoroperable to provide vibrational feedback in response to the pressuresensed by the sensor; and a processor, wherein the processor isconfigured to control the feedback in direct or inverse correlation withthe pressure detected by the sensor such that a characteristic of thefeedback is configured to increase or decrease in response to anincrease or decrease of sensed pressure.
 26. The system of claim 25,wherein a position of the foot is either: in contact with a surface, ornot in contact with a surface.
 27. The system of claim 25, furthercomprising a wireless communications module for transmitting and/orreceiving data.